Use of bacteriophages in cosmetic products

Po stoletju prekomerne uporabe antibiotikov se dandanes spopadamo z pozitivno povratno zanko evolucije, ki je omogočila preživetje bolj odpornih mikroorganizmov. Danes se zaradi odpornosti in nespecifičnega delovanja antibiotikov vračamo k odkritjem 20. stoletja. Dobro alternativo uporabi antibiotikov nam danes kaže alternativna uporaba litičnih bakteriofagov, ki so naravni ubijalci bakterijskih celic. Acne vulgaris je kronična vnetna bolezen, pri kateri ima za sam nastanek bolezni pomembno vlogo bakterija Cutibacterium acnes. Okužbe, ki jih povzroča C. acnes, bi v prihodnosti lahko zdravili s pomočjo bakteriofagov, vendar so bakteriofagi, kot biološki agensi, veliko bolj zahtevni za shranjevanje, kot kemične aktivne učinkovine. Cilj diplomske naloge je bilo v okolju poiskati in uspešno izolirati bakteriofage, ki okužujejo C. acnes in preveriti njihovo stabilnost v serumskih formulacijah. Serum je kozmetični izdelek in je fizikalno gledano viskozna tekočina z gladko homogeno strukturo, za katerega je značilna hitra absorpcija in sposobnost prodiranja v globlje plasti kože. Na podlagi pridobljenih rezultatov stabilnostne študije smo ugotovili, da imajo okoljski dejavniki in sestave serumov, ki so primerne za shranjevanje, zelo pomemben vpliv na stabilnost bakteriofagne koncentracije in da se koncentracije bakteriofagov, ki okužujejo C. acnes, dlje časa ohranjajo nespremenjene pri nižjih temperaturah shranjevanja ob ustrezni sestavi seruma in dovolj visoki začetni koncentraciji bakteriofaga.After a century of overuse of antibiotics, we are now dealing with a positive evolutionary feedback loop that has enabled the survival of more resistant microorganisms. Today, due to the resistance and non-specific action of antibiotics, we are returning to the discoveries of the 20th century. A good alternative to the use of antibiotics today is the alternative use of lytic bacteriophages, which in nature are natural killers of bacterial cells. Acne vulgaris is a chronic inflammatory disease in which the bacterium Cutibacterium acnes plays an important role in the development of the disease itself. In the future, infections caused by C. acnes could be treated with the help of bacteriophages, but as biological agents, they are much more demanding to store than chemical active agents. The aim of the thesis was to find and from the environment successfully isolate bacteriophages that infect C. acnes and to check their stability in serum formulations. Serum is a cosmetic product that is physically a viscous liquid with a smooth homogeneous structure, which is characterized by rapid absorption and the ability to penetrate deeper layers of the skin. Based on the obtained results of the stability study, we found that environmental factors and compositions of serums suitable for storage have a very important influence on the stability of the bacteriophage concentration. We also found that the concentrations of bacteriophages that infect C. acnes remain unchanged for a long time at lower storage temperatures with the appropriate composition of the serum and a sufficiently high initial concentration of the bacteriophage